195 55 r15 all around. As far as I know these are the correct size for the 1.6 model. But cruising at 60mph I am keeping level with hgv. Hgv can have tweaks to do 57mph but most are restricted to 56mph, except for stupid Asda and Argos trucks which I think are 52mph poor sods. This is normal driving, not racing down hill where the weight carries the truck beyond its restrictor.

According to mytyres, the 1.6 can have 185/55R15, 195/55R15 and 205/45R16.

Fitting 185's with a 195 setting in the BSI will make it fast.

Problem is, people think it's clever (and cheaper) to fit different profiles ... they don't realise the problems that causes. If your speedo is running fast, you are also clocking up more miles than reality ...